### Some Results on Post-Widder Operators Preserving Test Function $x^r$

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**Authors:**V. GUPTA AND G. TACHEV

**DOI:**10.46793/KgJMat2201.149G

**Abstract:**

In the present paper, we consider Post-Widder operators and its modiﬁed form which preserve the test function x

^{r}, r ∈ ℕ. We estimate direct results in terms of modulus of continuity for the modiﬁed operators. Also, some estimates for polynomially bounded functions and linear combinations are considered. Our estimates improve in some sense the previous results for the original Post-Widder operators.

**Keywords:**

Post-Widder operators, exponential functions, moments, polynomially bounded functions, linear combinations.

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